add AccountMessage

src/main/kotlin/ltd/hlaeja/library/accountRegistry/event/AccountMessage.kt

@@ -0,0 +1,9 @@
+package ltd.hlaeja.library.accountRegistry.event
+
+import java.util.UUID
+
+data class AccountMessage(
+    val userId: UUID,
+    val change: List<String>,
+    val timestamp: Long = System.currentTimeMillis(),
+)